1. Field of the Invention
The present invention relates to the field of insulating cover devices in general, and in particular to a two piece insulated and temperature controlled jacket for refrigerant cylinders.
2. Description of Related Art
As can be seen by reference to the following U.S. Pat. Nos. 5,377,495; 5,557,940; and 5,511,387, the prior art is replete with myriad and diverse refrigerant insulating arrangements.
While all of the aforementioned prior art constructions are more than adequate for the basic purpose and function for which they have been specifically designed, they are uniformly deficient with respect to their failure to provide a simple, efficient, and practical device for both insulating the exterior of a refrigerant drum and maintaining the temperature of the refrigerant drum within a desired temperature range when charging an air conditioner refrigeration and system during low ambient temperature conditions.
As anyone in the heating and air conditioning trade is well aware, low ambient temperatures reduce the effective PSIG within a refrigerant drum to the point that the air conditioner or refrigeration system cannot be effectively charged without first elevating the temperature of the refrigerant drum to increase the PSIG within the drum to acceptable levels.
For example, when changing out a 5 ton heat pump compressor at 10.degree. F. ambient temperature, the pressure of an R22 tank is 32.8 PSIG. Therefore, in order to charge this heat pump to the correct pressure, the charge will have to be weighed in; however, the internal pressure of the R22 tank is too low to accomplish this task.
Some of the prior art methods of elevating the temperature of the refrigerant drum have involved the use of hot water, placing the drum on a heated plate and/or subjecting the exterior surface of the refrigerant drum to the flame of a torch. All of these aforementioned methods are both impractical and extremely dangerous in that all refrigerant drums have a relief disc which discharges the refrigerant to the atmosphere under high pressure usually precipitated when the temperature of the tank exceeds 120.degree. F.
The ideal conditions for charging a refrigeration and air conditioning system occur when the external temperature of the drum is 90.degree. F. which produces an internal pressure within the drum of 168 PSIG so the acceptable temperature range for accomplishing this task will fall between 80.degree. F. and 100.degree. F. under most circumstances.
As a consequence of the foregoing situation, there has existed a longstanding need in the heating and air conditioning trades for a construction for raising the temperature of refrigerant drums or cylinders and the provision of such a construction is a stated objective of the present invention.